In the study by Kaiko et al., PAI-1 has been highlighted as a potential link between the epithelium and inflammation in the pathogenesis of IBD.11 The authors also demonstrated the discriminatory power of Serpin E1 [the gene encoding PAI-1] gene expression to distinguish between inflamed IBD biopsies versus non-inflamed/non-IBD biopsies. This evidence concerns the gene SERPINE1 and irritable bowel syndrome.